A barnacle-inspired interface for enhancing the interfacial properties of carbon fiber-reinforced poly(phthalazinone ether nitrile ketone) composite

Carbon fiber-reinforced thermoplastic resin composites (CFRTPs) have gained significant recognition in industries such as rail transportation, aerospace, and wind power generation. Among these composites, carbon fiber/poly(phthalazinone ether nitrile ketone) (CF/PPENK) composite is considered to be a high potential CFRTP because of the exceptional thermal stability and solubility of its matrix. However, due to the smooth surface of CF and the limited number of reactive groups in PPENK, the CF/PPENK composite demonstrated poor interfacial properties. In this study, drawing inspiration from the strong adhesive properties of barnacle structures, three different interfacial phases were fabricated on the CF surface. In these composites, polydopamine (PDA) particles acted as "barnacle glue" and three types of polyhedral oligomeric silsesquioxane (POSS) acted as "barnacles". The practicality and effectiveness of the design was initially verified by molecular dynamics simulations, which predicted optimal interfacial properties of the composite with PDA and 3-glycidyloxypropyl-POSS (EP) on the fiber surface (CF-PDA-EP/PPENK). X-ray photoelectron spectroscopy and scanning electron microscopy analyses confirmed the successful combination between the "barnacle structure" and CF. The experimental results aligned well with the simulation outcomes, validating that the interfacial properties of CF-PDA-EP/PPENK were optimal. Compared to the composites with unmodified fibers, the interlaminar shear strength and interfacial shear strength of CF-PDA-EP/PPENK were enhanced by 55.56 % and 210.73 %, respectively. This method offers an efficient and straightforward approach to the interfacial modification of the composites.